Kristen Bell has revealed that a song in 'Frozen 2' was inspired by her struggles with depression.

The 39-year-old actress sings the emotional tune 'The Next Right Thing' as her alter-ego Anna in the Disney sequel and she explained that the idea came from a chat with co-director Jennifer Lee about her mental health battles.

Speaking on the Disney+ series 'Into The Unknown: Making Frozen 2', Kristen said: ''When Anna thinks everyone around her has perished she has to look inward and realise what else is there to live for.

''And this mantra of 'do the next right thing' came out of a conversation that Jen and I had really early on about my anxiety and depression.

''I think The Next Right Thing, it really is for anyone who is feeling low and struggling and does not know what to do. Because the only thing you can do at those lowest moments is one step at a time.''

The 'Bad Moms' star added that she often follows the advice of the song when she is feeling down.

Kristen explained: ''When I'm experiencing that, for me, if I wake up and I'm feeling very low, all I've got to do is step out of bed and then, the next right thing is to brush my teeth, and the next right thing is to go and have a cup of coffee, and the next right thing is to wake my kids up.

''And I take those steps incrementally when the world and its problems seem too big for me to handle.''

Marc Smith, director of story on 'Frozen 2', recently revealed that Disney are yet to discuss the possibility of a third film.

He told Collider: ''We have not had that discussion.

''I think Frozen II is still too close to everyone's minds and ideas to, to think about what happens beyond... beyond that.''